The invention relates to an elastomeric flame and smoke retardant graft copolymer having excellent low temperature flexibility. More particularly, the invention relates to an elastomeric, flame and smoke retardant graft copolymer having excellent low temperature flexibility which consists of a backbone copolymer derived from a conjugated diene and butyl acrylate and a side chain polymer derived from vinylidene chloride.
Graft copolymers having some similarity in composition or structure to those of the present invention have been described in the prior art. Thus, French Pat. No. 1,276,804 to Michel and Peyrade (1962) discloses the preparation in emulsion of a graft copolymer consisting of a vinyl polymer backbone (i.e., polyvinyl chloride), and a side chain polymer derived from 1,3-butadiene or a mixture of 1,3-butadiene and a vinyl monomer such as methyl methacrylate.
French Pat. No. 1,534,628 assigned to CIBA Limited (1968) discloses the preparation in emulsion of a graft copolymer consisting of a copolymer backbone derived from 1,3-butadiene and a vinyl monomer such as styrene, acrylonitrile, methyl methacrylate or alpha-methylstyrene and a side chain copolymer derived from acrolein, an alkyl acrylate and another vinyl monomer such as vinylidene chloride or vinyl acetate.
U.S.S.R. No. 219,201 to Fridland, et al (1968) discloses the preparation in emulsion of a graft copolymer consisting of a copolymer backbone derived from 1,3-butadiene and vinylidene chloride and a side chain copolymer derived from 1,3-butadiene and vinyl pyridine or betachloroethyl methacrylate.
U.S. Pat. No. 4,187,202 to Kondo, et al discloses the preparation in emulsion of graft copolymers consisting of a rubbery backbone polymer such as natural rubber, styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, isoprene, chloroprene, acrylic rubber, ethylenepropylene-diene terpolymers, and ethylene-vinyl acetate copolymer and a side chain polymer or copolymer derived from vinyl, vinylidene (e.g., vinylidene chloride) and vinylene monomers or mixtures thereof.
While, as mentioned heretofore, the above prior art patents disclose graft copolymers which are somewhat similar in composition or structure to the graft copolymers of this invention, they do not disclose graft copolymers having the specific composition and structure of the graft copolymers of the present invention. Moreover, none of the aforementioned prior art patents disclose or suggest that the graft copolymers described therein exhibit the combination of flame and smoke retardant characteristics and low temperature flexibility which are extremely important characteristics of the graft copolymers of this invention.